Self-contained lifting module for the mobile bottom of a swimming pool

ABSTRACT

A lifting module for the mobile rigid bottom of a swimming pool, including: a) a driving housing controlling the immersion and lifting movements at a single point of the mobile bottom; b) at least one peripheral guiding member of the mobile bottom; c) at least one transmission member connected to the driving housing on the one hand and to the single point of the mobile bottom on the other hand, the lifting module being totally self-contained in that it is free of any mechanical link with any other lifting apparatus acting at another lifting point of the mobile bottom.

Legislation relating to safety in and around swimming pools has become increasingly rigorous over the last few years, leading to the arrival in this occupational sector of numerous accessories, methods or devices responsible for ensuring safety on the way to pools or also sounding an alarm when a body falls into the water.

In this sector of the market it is therefore common to encounter various models of barriers, walls or railings designed especially to prevent children from reaching the pool of the swimming pool alone without supervision. This physical means preventing access does not always ensure complete safety as, most of the time, it cannot effectively prevent anyone from climbing over it.

Nowadays, numerous other devices are commercially available, such as for example audible alarms designed to signal, immediately around the pool, when a body or object falls into the water. Unfortunately, these devices often go off when it is too late, i.e. when the child has fallen into the water and is already in a distressed state. Saving the individual concerned then depends firstly on the audible alarm being heard by someone nearby, which can sometimes be risky when there are other surrounding noises and secondly on the speed of action of those hearing the alarm signal, who may be quite some distance from the pool at that precise moment.

Certain professionals therefore propose various devices making it possible to completely cover the surface of the water outside bathing times, by unwinding or sliding a protective screen well and truly in contact with the water or very slightly above it.

Although this kind of method seems highly effective for preventing leaves and other light plant waste from falling into the water, the unwound or unfolded screen is often insufficiently rigid to hold the weight of a child who has accidentally fallen into the pool for a long enough time.

At present, it appears that the most effective of the swimming pool safety systems is the presence of a mobile rigid bottom which, completely immersed in the depths of the pool during bathing times, is lifted again when bathing finishes in order to cover the entire surface of the swimming pool, thus offering complete safety with a particularly suitable rigidity and resistance to falls.

Nevertheless, depending on the system, this type of mobile bottom device has certain technical drawbacks such as, for example, the occupation at the floor of the pool of a large volume between the mobile bottom and the floor of the pool, for the positioning and the utilization of immersed mechanisms. In such a case, the useful depth of the pool of the swimming pool is substantially reduced.

On the other hand, numerous swimming pools have a sloping bottom in order to offer swimmers, a shallow pool at one end (shallow end) and a deeper pool at the other end (deep end).

The rigidity of the mobile bottom is a major safety factor in this method. In fact, depending on whereabouts the body falls onto the mobile bottom, the latter may bend locally sufficiently to allow the body to pass under the mobile bottom, thus virtually inevitably resulting in drowning.

Several techniques have been implemented by professionals in order to reconcile the rigidity of the mobile bottom with its mobility in the water during immersion or lifting.

Most often, the mobile bottoms encountered commercially or in the state of the art have orifices facilitating the passage of water through the mobile bottom. This development substantially reduces resistance to movement and facilitates mobility.

On the other hand, current regulations precisely define the dimensions of a peripheral space between the edge of the mobile bottom and the walls of the pool. The main purpose of this space is to facilitate the movements of water during the movements of the mobile bottom in the pool while preventing accidents which could be caused by a swimmer's foot becoming caught in this space.

It therefore appears that maximum safety is achieved by multiplication of the points for anchoring and lifting the mobile bottom which guarantees optimum rigidity and good resistance to a falling body. This finding is all the more verifiable, the greater the surface area of the swimming pool or the more unusual its shape.

However, the state of the art most often shows a limited number of lifting points, such as for example, four lifting points distributed at the four corners of the swimming pool when the latter is square or rectangular in shape.

The limitation of the number of lifting points is most often due to the complexity of the devices put in place to act simultaneously on said lifting points. The kinematics utilized are all the more complex, the higher the number of lifting points for the mobile bottom.

For example, in the state of the art it is possible to find devices acting by means of pneumatic or hydraulic jacks cooperating with a set of cables and pulleys arranged all around the swimming pool. This type of device with heavy kinematics involves significant and expensive fittings, inside, outside and in proximity to the pool which inevitably leads to incorrect operation, breakdowns, interventions on buried areas and consequently to increased installation and maintenance costs.

Similar devices also combine the integration of jacks and networks of cables and pulleys in the actual structure of the mobile bottom, which adds to the abovementioned drawbacks that of the immersion of active mechanical components in chlorinated aquatic environment.

All the devices now present in the state of the art involve the immersion of metal cables in the water, said cables being actuated by means of conventional pulleys buried outside the pool or themselves immersed in the water of the pool.

The purpose of the present invention is to substantially improve the elements for manoeuvring a mobile bottom inside a pool and thus considerably reduce the involvement of accessories, fittings and work in the construction of a swimming pool and to reduce its cost as a result.

To this end, a subject of the invention is a lifting module for the mobile rigid bottom of a swimming pool, characterized in that it comprises:

-   -   a) a drive housing controlling the immersion and lifting         movements at a single point of the mobile bottom,     -   b) at least one peripheral guiding element of the mobile bottom,     -   c) at least one transmission element connected to the drive         housing on the one hand, and to said point of the mobile bottom         on the other hand,     -   the lifting module being completely self-contained in that it is         free of any mechanical link with any other lifting means acting         at another lifting point of the mobile bottom.

Thus the self-contained lifting module according to the invention is structurally very simple, unlike numerous devices of the state of the art which have a single central driving unit acting on several lifting points via complex installations and bulky mechanisms (numerous cables, pulleys, jacks, levers etc.), a technique which involves heavy work and fittings in the pool and outside the pool and high costs and installation times as a result. The self-contained lifting module according to the invention is arranged in as many units as necessary all around and outside a swimming pool, in order to allow the total immersion and lifting of a mobile bottom. The individual lifting modules installed around the pool are strictly identical. They can be controlled independently of each other. After installation, simple adjustments are sufficient to synchronize the individual self-contained lifting modules in order to achieve the sought cooperation.

By limiting and simplifying its active elements, the device of the present invention considerably reduces the risks of breakdowns, and maintenance and repair operations. It is suited to all types of swimming pool with rigid walls, all pool shapes and all attitudes of pool floors. It does not affect the volume of water in the pool and can be utilized with all types of mobile bottoms.

Before the manufacture of a swimming pool, the mobile bottom is studied in accordance with current regulations and the characteristics of the pool, such as for example the shape, dimensions, depth, attitude of the floor and access. The quantity and location of the lifting points are determined as a function of the characteristics of the mobile bottom to be moved.

According to other advantageous features of the invention, the drive housing comprises an electrically driven motor, connected to the transmission element by driving means such as a set of pulleys or accessories or reduction means, in order to bring about the immersion or lifting of the mobile bottom in the pool of the swimming pool.

According to yet other advantageous features of the invention, the drive housing comprises a hydraulically driven motor, connected to the transmission element by driving means such as a set of pulleys or accessories, in order to bring about the immersion or lifting of the mobile bottom in the pool of the swimming pool.

Such a motor offers a power and an operating torque perfectly suited to this use. Moreover it makes it possible to dispense with a braking system preventing the movement of the mobile bottom.

According to yet other advantageous features of the invention, the guiding element is a rail having the general shape of a profile arranged substantially vertically along a vertical wall delimiting the pool of the swimming pool, the mobile bottom being provided with cooperating peripheral sliding and/or winding means supported on one surface of the rail.

According to yet other advantageous features of the invention, the guiding element is suspended at its top end by a mounting plate mounted on a top edge of the swimming pool, constituted in particular by a structural element and/or a curb.

According to yet other advantageous features of the invention, the guiding element is not fixed to the vertical wall against which it is arranged.

According to yet other advantageous features of the invention, the guiding element is made of stainless material and comprises a foam coating on a surface facing the vertical wall, in order to ensure it a non-aggressive contact with the latter.

According to yet other advantageous features of the invention, the section of the guiding element is corrugated in shape and provided with a central reinforcement cooperating with the sliding and/or winding means of the mobile bottom, the reinforcement being edged with lateral bosses ensuring the guiding of the mobile bottom in the reinforcement.

According to yet other advantageous features of the invention, the transmission element is constituted by a “marine” type strap.

According to yet other advantageous features of the invention, an angle pulley is arranged in the upper part of the guiding element and/or on the mounting plate, the transmission element connecting the drive housing with the lifting point running over this angle pulley.

A subject of the invention is also a lifting installation for the mobile rigid bottom of a swimming pool, comprising several lifting modules having all or some of the previous features, the lifting modules being arranged at several separate lifting points of the mobile bottom, distributed around the periphery of the latter.

According to other advantageous features of the invention, the installation comprises a device for adjusting and synchronizing the operation of the different lifting modules.

According to yet other advantageous features of the invention, the adjustment and synchronization device is adapted to produce different lifting or immersion travels for the different respective lifting points of the mobile bottom, such that the latter can be placed against the floor of the swimming pool whatever the angle of inclination of the attitude of the floor of the pool of the swimming pool.

A subject of the invention is also a swimming pool comprising a mobile rigid bottom, as well as a lifting installation for the mobile bottom having all or some of the previous features, at least one drive housing being mounted on an upper edge of the swimming pool, such as a structural element and/or a curb, so that it protrudes beyond this upper edge.

According to other advantageous features of the invention, the swimming pool comprises a lifting installation for the mobile bottom having all or some of the previous features, at least one drive housing being mounted outside an upper edge of the swimming pool, so that at least part of the drive housing is buried in the ground substantially flush with said upper edge.

The invention will be better understood on reading the following description of a non-limitative embodiment of the invention and in the light of the attached drawings, in which:

FIG. 1 represents a partial perspective view of the lifting module according to the invention,

FIG. 2 is an overall perspective view of a swimming pool provided with six lifting modules positioned at six lifting points for a mobile bottom,

FIG. 3 is a partial perspective view of a lifting module according to FIG. 1 mounted on the edge of a swimming pool, the drive housing not being shown,

FIGS. 4 and 5 are views similar to FIG. 3 illustrating two embodiments of the invention, in which the drive housing is respectively at least partly buried outside the edge of the swimming pool, and mounted on top of the outer edge of the swimming pool,

FIG. 6 is a section viewed from above of a winding and/or sliding zone of a peripheral edge of the mobile rigid bottom with a guiding element of the module according to the invention,

FIG. 7 is a perspective view of a lifting module according to the invention fitted according to another embodiment, in which the drive housing is situated under the curb of a swimming pool,

FIG. 8 is a perspective view of a guiding element according to another embodiment of the invention, the guiding element having a C-shaped section provided with an opening allowing the movement of an attachment system of the mobile bottom along this guiding element.

FIG. 9 is a perspective view of a guiding element according to yet another embodiment of the invention, the guiding element being provided with an opening the edges of which, made of flexible material, on the one hand move apart in order to allow the movement of an attachment system of the mobile bottom along this guiding element made of flexible material, and on the other hand close again after the attachment system has passed.

FIG. 10 is a perspective view of the guiding element according to the invention installed according to another embodiment, which consists of being flush-mounted in a wall of the pool of the swimming pool,

FIG. 11 is a partial view of the transmission element according to the invention, comprising an identical or different fitting at each of its ends, and

FIG. 12 is a partial view of the transmission element of the invention equipped with a device at least one end, making it possible to limit friction and facilitate sliding/winding against the guiding element.

FIG. 1 shows the main elements constituting a lifting module 100 according to the invention. The latter comprises a drive housing A controlling the (downward) immersion and lifting movements of the mobile bottom 3. The lifting module 100 also comprises a guiding element B of a peripheral zone of the mobile bottom 3. The lifting module 100 also comprises a transmission element C connected to the drive housing A on the one hand, and to the mobile bottom 3 on the other hand.

According to the invention, the lifting module 100 acts at a single lifting point. By the concept of a “lifting point” is meant a restricted zone at the periphery of the mobile bottom 3, of the order of a few centimetres or decimetres. According to an essential aspect of the invention, the transmission element C is therefore connected to the mobile bottom 3 at a single lifting point. An immersion (or descent) or lifting movement is given to the mobile bottom 3, by a set of lifting modules 100 which are arranged in as many units as necessary, on the edges of the Pool D of the swimming pool. FIG. 2 illustrates the installation of six lifting modules 100 acting at six lifting points of the mobile bottom 3. The number and distribution of the lifting modules are a function of the load to be supported and driven, which depend directly on the weight of the mobile bottom 3, but also on the shape of the mobile bottom 3. It is important to aim at a balanced distribution, as homogeneous as possible, of the loads to be borne by each of the lifting modules 100.

According to the invention, the lifting modules 100 of the installation are activated by an adjustment and synchronization device. The latter is adapted to controlling lifting travels which may be similar or different at each lifting point. Thus, the individual modules 100 can control the movement of the mobile bottom 3 while keeping it substantially horizontal whatever its height. The individual modules 100 can control the movement of the mobile bottom 3 by inclining it at a desired angle, for example so as to follow a floor of the swimming pool which would itself be inclined with respect to a horizontal plane.

The drive housing A comprises a motor M, M′ connected to the transmission element C. This connection is ensured by driving means (not shown) such as a set of pulleys or accessories or reduction means, which are standard and of a design well within the scope of a person skilled in the art.

In a first embodiment of the invention, the motor M is an electrically driven motor. The motor is connected to a standard electrical circuit which complies with current regulations relating to the power supply to outside equipment. By way of example, for a mobile bottom weighing 1500 kg, a lifting speed of 0.03 m/s, a pulley radius of 0.05 m at the drive shaft outlet, a linear acceleration of 1 m/s², an efficiency of 0.6 and a lifting distance of 2.5 m, a necessary mechanical power is obtained of the order of 75 W for a nominal torque of 125 Nm. Assuming that there are four modules, therefore four electric motors, the necessary power for each is divided by four. Allowing a safety factor of the order of 1.5, we obtain a mechanical power per unit of the order of 37.50 W for a torque rating of 41.67 Nm. An electric motor coupled with a reduction gear (gear motor) is perfectly suitable. A gear motor makes it possible to obtain high useful torque capacities by the addition of a mechanical reduction.

In a second embodiment, the motor M′ is driven hydraulically. This latter case allows a greater power and operating torque than electric motorization; a hydraulic motor also dispenses with the provision of braking means capable of blocking the movement of the mobile bottom 3. In order to limit the hydraulic passages, an independent hydraulic motor (pump unit) is preferred for each lifting module. Each motor is hydraulically independent and has its own fluid reserve. Only one power supply is to be routed as far as the drive housing A for the pump motor. By way of example, a pump motor suitable for each module can be of the “CASAPPA Polaris 10 series” © pump type. The torque developed (at 100 bar) is 1.35 Nm. The flow rate at 700 rpm is 0.68 l/mn. The minimum operating speed is 650 rpm which involves the implementation of a reduction ratio of 132.

The casing 1 constituting the drive housing A is made of a rigid material, sufficiently solid to support the weight of one or two persons resting thereon. This material is capable of resisting corrosion, due to its chemical composition, or due to a surface treatment.

The drive housing A comprises on its upper part an access panel T making it possible to install its components, but also to intervene directly in the mechanism for fault rectification or operation adjustment.

The drive housing A also contains an indicator 2, preferably visual, making it possible to precisely identify at the actual lifting point, the exact position of the mobile bottom 3 with respect to the floor 4 of the swimming pool. This indicator 2 for locating the mobile bottom 3 facilitates the adjustment and the synchronization of the different lifting modules 100 with each other. It thus becomes possible for the mobile bottom 3 to be placed correctly against the floor 4 of the pool D when the latter is in the bottom position, even when the floor 4 of the pool D is inclined. In the top, so-called safety, position, the mobile bottom 3 adjusts automatically and due to the control settings has a perfectly horizontal attitude.

With reference to FIGS. 1 and 6, the guiding element B is a rail having the general shape of a profile arranged substantially vertically along a vertical wall 5 delimiting the swimming pool D. The mobile bottom 3 is provided with sliding and/or winding means 6, typically balls (as illustrated in FIG. 6) or rollers maintained at the periphery of the mobile bottom 3, which cooperate in contact with the guiding element B. The guiding element B has a section corrugated in shape. This section is provided with a central reinforcement receiving the sliding and/or winding means 6, this central reinforcement is edged with lateral bosses channelling the sliding and/or winding means 6 during their movement along the guiding element. This corrugated shape is particularly suited to optimum guiding of the mobile bottom, while being extremely simple in design and installation.

As shown by FIG. 3, the guiding element B is suspended by its upper end from a mounting plate 7. The latter is mounted on an upper edge of the swimming pool, typically constituted by a structural element of the swimming pool or a curb E. The mounting of the plate 7 to the structure or the curb E can be ensured by mounting bolts or by bonding or by any equivalent appropriate means.

The guiding element B is connected to the plate 7 by means which can be articulated, for example to allow easy packaging and transport (the plate—guiding element assembly being flat or folded onto itself), and for rapid positioning on the edge of the swimming pool (the guiding element B is positioned at 90° with respect to the plate 7).

The 90° angle between the plate 7 and the guiding element B can be locked by appropriate means, for example by a system of pins. In another embodiment, the guiding element B and the plate 7 can be rigidly fixed at 90° to each other automatically.

According to the invention, the guiding element B is not fixed to a vertical wall 5 against which it is placed. The guiding element B is simply oriented to follow this wall 5. Once the mobile bottom 3 is put in place, the sliding and/or winding means 6 only have the effect of abutting the guiding element, which helps to hold it against the wall 5 of the pool. Retaining means of the guiding element are not necessarily provided.

The guiding element is made of stainless material, such as stainless steel.

In order to ensure a non-aggressive contact between the guiding element B and the wall 5 of the pool D, the guiding element B, can comprise on its surface facing the wall 5, a coating or a layer 8 of plastic material, rubber or foam (FIG. 3).

According to another aspect of the invention, the transmission element C connected to the motor M, M′, is also connected to the lifting point of the mobile bottom 3 by appropriate attachment means, in order to transmit the pulling forces to this lifting point.

Advantageously, the transmission element C is a “marine” type strap, made of synthetic material, for example plastic or nylon or similar, particularly suited for use in a chlorinated aquatic environment. Such a strap has extremely high-performance traction behaviour characteristics for a relatively reduced thickness, which minimizes its bulk in the drive housing A when it is wound up.

The strap C is provided at each of its ends with an arrangement 13 allowing on the one hand its positioning and its anchoring to one of the internal driving elements with the drive housing A, and on the other hand its fixing to the attachment means making it possible to connect it to the mobile bottom 3.

On the other hand, the strap C is equipped with one or more inserted elements 14 intended to limit friction while moving along the guiding element B.

According to the invention, the drive housing A can be installed in different ways. According to a first variant of the invention, illustrated in FIG. 4, the housing A is mounted outside an upper edge E of the swimming pool, so that the bottom part of the housing A is buried in the ground, set back from the pool D.

According to a second variant of the invention, illustrated in FIG. 5, the housing A is mounted on top of an outer edge E of the swimming pool. The housing A can thus itself constitute a block from which it is possible to dive into the swimming pool. The housing A can also be integrated with a block of this type.

An angle pulley 9 can be provided at the junction of the plate 7 and the guiding element B, so as to promote the winding of the transmission element C which must form a transmission angle in this zone. In the same way, it is possible to provide an angle pulley 9′ in other zones passed through by the transmission element C, for example close to the drive housing A (FIG. 1).

With reference to FIG. 6, the sliding and/or winding means 6, typically balls in the example illustrated, can be mounted in a mobile fashion in a corresponding recess 10 arranged at the periphery of the mobile bottom 3, so as to take up any play between the wall 5 of the pool D and these means 6. In the example illustrated, the ball protrudes by approximately one-third of its diameter. A return spring 11 tends to push the ball back towards the peripheral edge of the mobile bottom 3. Trapping means 12 are situated at the mouth of the recess 10 in order to prevent the sphere escaping from its recess.

Another installation variant of the drive housing A can also be envisaged, as shown by FIG. 7. The housing is installed in a recess provided under the curb E of the swimming pool. This installation method however requires a more onerous adaptation of an existing swimming pool (compared to the installations of FIGS. 4 and 5), for receiving the lifting module. It is also possible to provide visual reference marks on the curb E or close by, in order to precisely know the location of the drive housings A concealed under the curb E.

A lifting module according to the invention, due to its simplicity, and the actual principle of self-containment of the module, is perfectly suited to installation on existing swimming pools, the side walls of which are substantially vertical, without requiring excessive equipment or fitting costs.

Of course, the invention is not limited to the means which have just been described and comprises all the technical equivalents.

In particular, the transmission element can be a cable (not shown), replacing the strap, without this calling into question other features of the invention.

Concerning the guiding element, it is also possible to provide that the rail B′ is inserted and fixed to the wall of the pool D, for example by means of mounting bolts, by bonding or by means of clips, which make it particularly detachable.

In an embodiment variant illustrated in FIG. 8, the section of the guiding element B′ can generally be C-shaped, a central part of which is placed against the wall 5 of the swimming pool D. The opening of this C-shaped section, over the whole length of the rail, allows the movement of the attachment means F, which joins the bottom end of the transmission element C to the mobile bottom 3, over the whole length of the rail.

The guiding element B′ can be made entirely of plastic material, flexible or rigid, compatible with the chlorinated aquatic environment. With reference to FIG. 9, this element can also comprise edges or lips delimiting the opening of the C-shaped element, which are relatively flexible, so as to open while the attachment means Fl are passing, and to close again by elasticity after they have passed. This closing effect offers swimmers a smooth and non-aggressive surface. According to another variant (not shown), the body of the guiding element can be made of a first, relatively rigid, material whilst the edges or lips of the opening of the C-shaped element are made of a second, more flexible, material allowing them to open and close under the effect of the attachment means F1.

According to yet another embodiment of the invention, illustrated in FIG. 10, the guiding element B″ is positioned so as to be embedded or flush-mounted in the internal wall 5 of the pool D. This arrangement offers surfaces of the guiding element B″ which are flush with the wall 5 of the pool, making the guiding element particularly non-aggressive to swimmers. This arrangement however assumes the provision of this integration of the guiding element when the pool D of the swimming pool is manufactured. 

1. A lifting module for the mobile rigid bottom of a swimming pool, comprising: a) a drive housing controlling the immersion and lifting movements at a single point of the mobile bottom; b) at least one peripheral guiding element of the mobile bottom (3); c) at least one transmission element connected to the drive housing on the one hand, and to said single point of the mobile bottom on the other hand; the lifting module being completely self-contained in that it is free of any mechanical link with any other lifting means acting at another lifting point of the mobile bottom.
 2. The lifting module according to claim 1, characterized in that the drive housing comprises an electrically driven motor, connected to the transmission element by driving means such as a set of pulleys or accessories or reduction means, in order to bring about the immersion or the lifting of the mobile bottom in the swimming pool.
 3. The lifting module according to claim 1, characterized in that the drive housing comprises an electrically driven motor, connected to the transmission element by driving means such as a set of pulleys or accessories, in order to bring about the immersion or the lifting of the mobile bottom in the swimming pool.
 4. The lifting module according to claim 1, characterized in that the guiding element is a rail having the general shape of a profile arranged substantially vertically along a vertical wall delimiting the pool of the swimming pool, the mobile bottom being provided with at least one of cooperating peripheral sliding and winding means supported on one surface of the rail.
 5. The lifting module according to claim 4, characterized in that the guiding element is suspended at its top end by a mounting plate fixed to a top edge of the swimming pool, constituted in particular by a structural element and/or a curb.
 6. The lifting module according to claim 5, characterized in that the guiding element is not fixed to the vertical wall against which it is arranged.
 7. The lifting module according to claim 4, characterized in that the guiding element is made of stainless material and comprises a foam coating on a surface facing the vertical wall, so as to ensure it a non-aggressive contact with the latter.
 8. The lifting module according to claim 4, characterized in that the section of the guiding element is corrugated in shape and provided with a central reinforcement cooperating with the sliding and/or winding means of the mobile bottom, the reinforcement being edged with lateral bosses ensuring the guiding of the mobile bottom in the reinforcement.
 9. The lifting module according to claim 1, characterized in that the transmission element is constituted by a “marine” type strap.
 10. The lifting module according to 1, characterized in that a guide pulley is arranged at least one of in the upper part of the guiding element and on the mounting plate, the transmission element connecting the drive housing to the lifting point running over this guide pulley.
 11. A lifting installation for the mobile rigid bottom of a swimming pool, comprising: several lifting modules arranged at several separate lifting points of the mobile bottom, distributed around the periphery of the latter.
 12. The lifting installation according to claim 11, characterized in that it comprises a device for adjusting and synchronizing the operation of the different lifting modules.
 13. The lifting installation according to claim 12, characterized in that the adjustment and synchronization device is adapted to produce different lifting or immersion travels for the respective different lifting points of the mobile bottom, so that the latter can be placed against the bottom of the swimming pool whatever the angle of inclination of the floor of the swimming pool.
 14. A swimming pool comprising: a mobile rigid bottom including a lifting installation of the mobile bottom according to claim 11, at least one drive housing being mounted on an upper edge of the swimming pool, such as at least one of a structural element or a curb, so that said drive housing protrudes beyond this upper edge.
 15. A swimming pool comprising: a mobile rigid bottom and including a lifting installation of the mobile bottom according to claim 11, at least one drive housing being mounted outside an upper edge of the swimming pool, so that at least part of the drive housing is buried in the ground substantially flush with said upper edge. 